sample data above, The formula is to work out how many items in the Av column is above or below 10% of the Tot column per week but return only the value for the best week and only interested in weeks 1 to 7.
In the data above the best week would be week 6. 14 items total this week so the AV column to hit 10% would be 1.4. 10 are in the Av column so this is 8.4 above what is required rounded up to return a value of 9
the formula needs to do the calulation above basically for each week 1-7 and return the highest value.